Sadly, one-third of adults and 17% of children in the U.S. are obese, and weight loss drugs have become a big business. The Food and Drug Administration has not approved any new prescription medications for obesity since 1999, but this week, the agency decided to reverse a ruling against the controversial weight-loss drug, Qnexa. The drug’s approval had been rejected in 2010 due to risk of heart problems and birth defects. A final ruling won’t be available until later this year. So what, exactly, are these miracle dieting pills and what do they do to your body to help you lose weight? We break down the available prescription and over-the-counter drugs for weight loss. If you are considering using any of these, consult with your doctor or healthcare provider first.

Tenuate

Generic Name: Diethylpropion -Approved by the FDA for short-term use only ( less than 12 weeks) -Prescription only How it works: It’s a stimulant similar to an amphetamine (i.e. Adderall) that stimulates your central nervous system and decreases your appetite. Side effects: Fast or irregular heart rate, dizziness, restlessness

Adipex

Generic Name: Phentermine -Approved by the FDA for short-term use only (less than 12 weeks) -Prescription only How it works: Another stimulant similar to an amphetamine (i.e. Adderall) that stimulates your central nervous system and decreases your appetite. Side effects: Increased blood pressure, heart palpitatons, insomnia, dizziness, restlessness

Qnexa

Generic Name: Phentermine and Topiramate -Currently under review by the FDA (will be for long-term use) -Prescription only How it works: Phentermine is a stimulant that decreases appetite, while Topiramate is a drug typically used to treat epileptic seizures that carries weight loss side effects. Side effects: Tingling, dry mouth, constipation, increased heart rate, birth defects

Xenical

Generic Name: Orlistat -Approved by FDA for long-term use -Prescription only How it works: Blocks absorption of some dietary fat in the intestines so that it comes out in your waste (Read: Greasy bowel movements) Side effects: gastrointestinal issues (cramping, diarrhea, oily spotting), rare cases of severe liver injury reported

Alli

Generic Name: Orlistat, reduced-strength -Approved by FDA for long-term use -Over-the-counter How it works: Blocks absorption of some dietary fat in the intestines so that it comes out in your waste (Read: Greasy bowel movements) Side effects: gastrointestinal issues (cramping, diarrhea, oily spotting), rare cases of severe liver injury reported